(1) Technical Field
The invention relates to a material handling container of the type for packaging, shipping, and inventorying goods. More specifically, the invention relates to a reusable, molded thermoplastic container which is collapsible when empty and stackable in either the collapsed or upright position in order to reduce the space required to ship or inventory goods stored in the container.
(2) Description Of The Prior Art
Material handling containers used for packaging, shipping and inventorying goods are well known in the art. For example, U.S. Pat. No. 4,591,065 issued to Foy on Mar. 27, 1986; U.S. Pat. No. 4,917,255 issued to Foy et al. on Apr. 17, 1990; U.S. Pat. No. 4,923,079 issued to Foy; U.S. Pat. No. 4,674,647 issued to Gynge et al. on Jun. 23, 1987; U.S. Pat. No. 4,775,068 issued to Reiland et al. on Oct. 4, 1988; and U.S. Pat. No. 5,094,356 issued to Miller on Mar. 10, 1992 all disclose collapsible containers having a base and four walls which are hingedly connected to the base. The walls are moveable between a collapsed position where the walls are folded one on top of the other and an upright position where the walls extend vertically upward from the base to define an interior of the container.
Containers of the type disclosed in the patents listed above are made of plastic and are generally the largest of their class having dimensions ranging from approximately 40-45 inches in width, .times. approximately 48 inches in length, .times. approximately 25-39 inches in height. Typically, in the prior art, each wall and base of such containers are molded separately using a structural foam molding process. Mold tooling costs are an important factor in the design of a collapsible container. Reducing the number of tools required to mold the walls and base of the container can lower the up-front capital expenditures and therefore the cost of the container. However, it is not uncommon that five sets of tools are required to mold containers in the prior art. For example, the container disclosed by Foy et al. in their '255 patent includes a pair of sidewalls and a pair of end walls, each of which is hingedly connected to the base along a different horizontal plane spaced vertically from the horizontal planes defined by the three hinges of the other walls. The walls can thus be folded over into overlapping vertical spaced relationship with respect to one another when collapsed as shown in FIGS. 12-14 of this patent. While Foy et al. maintain this feature increases the structural integrity of the containers when stacked, it also necessitates a different set of tools for each wall resulting in high tooling costs. Still further, this feature necessitates that an operator fold the walls in a specific sequential order. This has proved to be inconvenient in the field.
Accordingly, there is a need for a container having walls which may be molded from common tools which are hinged to the base on common planes and which can be folded non-sequentially while still maintaining structural integrity when the containers are stacked one upon the other.
The subject invention overcomes all of these deficiencies in the prior art and meets the above-identified needs in a durable, light-weight, container wherein the walls of the container can be molded using common tools thus reducing the cost of manufacturing the container.